We previously showed that the 5A peptide can promote cholesterol efflux by the ABCA1 transporter and reduce atherosclerosis in animal models. The peptide was licensed to KineMed Inc, who received a RAID grant for performing preclinical toxicology studies, which have commenced. We have done additional structure function studies on the 5A peptide and identified 2 key hydrophobic residues in the hinge region of this bi-helical peptide for it to be able to promote cholesterol efflux. Based on this finding, we developed a new membrane solubilization model for how apolipoprotein mimetic peptides interact with membranes and promote cholesterol efflux.